A presentation of student research

Written in collaboration by Samantha Robertson, Dan Huddleston, and Stephan Hearn

Introduction

The Port Kembla wave energy station was an oscillating wave energy test station proposed to be developed by Oceanlinx in New South Wales, Australia as a 500 kilowatt facility. The project was conducted in two stages, where distance from shore was manipulated so that the stations could collect energy and provide data for future designs. The initial phase of the Port Kembla energy station was commissioned in 2005 and remained active until 2009. This project was the first fully operational archetype designed by Oceanlinx, and was dubbed greenWAVE Mk1, a shallow water energy device that capitalized on near shore transmission capabilities. The second phase was commissioned in February of 2010 and only remained functional until March 2010. This project was called the blueWAVE Mk3-Pre Commercial, which was a deep sea floating device connected to the utility grid and designed as an original prototype for future deep water wave energy stations (Falcão, 2014.) The blueWAVE Mk3 devices is the focus of this case study (Figure 1.) Unfortunately, the Mk3 was not proven successful under turbulent ocean conditions and subsequently fell apart due to adverse weather conditions. Currently, the decommissioning of the Mk3 has sparked national controversy regarding Oceanlinx’s timeline for removing the wreckage (Figure 2.)

Figure 2: The Mk1 while in operation (left) and the wreckage that remains today (right) (Illawarra Mercury)

While the Port Kembla wave energy project was a combination of both public and private investment, the Australian Federal Government exhibited the most enthusiasm for translating plans into grid-linked energy production. In 1999, two years after Oceanlinx was established, the project received a $750,000 grant by the Federal Government. In 2004, one year prior to the commissioning of the station, Oceanlinx was awarded another $1.21 million by the Australian Federal Government for research and development in conjunction with the National Wave Energy Optimization Program. The first major private investment was then granted a year later in 2005, when the Center for Energy and Greenhouse Technologies supplied $500,000 (Oceanlinx, 2012.)

Installation Characteristics

The environmental conditions of Port Kembla make it an ideal geographic location for a deep ocean wave energy device. Port Kembla is located along Australia’s western coast, just south of the capital Sydney. Along Australia’s western coastline flows the East Australian Current , an oceanic current that is extremely powerful, moving as much as 30 million cubic meters of water per second in a space that covers as much as 100 kilometers in width and 500 meters in depth (NASA.) The East Australian Current (EAC) is a stream of warm water and the western boundary of the South Pacific gyre, it is also the only oceanic current that connects two oceans, serving as a link between the Pacific and Indian ocean gyres (Ridgeway, et all.) Consequently, the EAC is characterized by strong swells at various depths and thus provides natural conditions for wave energy conversion. However, the EAC is also dominated by mesoscale eddies, elements of fluid dynamics that reverse the current flow in a swirling motion (Ridgeway, et all.) As a result, these eddies have the potential to create highly variable flows of current strength and direction (Ridgeway, et all.) This sparks discussion concerning device resiliency and energy reliability under amidst variable ocean conditions, which will be discussed in more detail when assessing the environmental impacts.

During its brief production period, the Mk3 produced 500 kilowatts of power for 500 homes on the grid (Oceanlinx.) It was Australia’s first deep ocean wave energy device that successfully connected to the grid (Oceanlinx.) A unique function of the Mk3 was that it produced desalinized water while also creating energy. In fact, the device purified 2,000 liters of fresh drinking water each day (NCCARF.) Mk3 was located 100 meters from shore and consisted of eight floating oscillating wave column (OWC) devices (NCCARF.) Although the device rested on the surface of the water, the mooring lines connected to transmission devices located ten meters below the surface (NCCARF.) The entire cost of the project was approximately $4.7 million.

Environmental Impact Assessment

Although the MK3 prototype was only online for two months, it did provide power to the grid at a successful rate and seemingly caused no adverse environmental effects witnessed. This information is published the Tethys website, which is designed track and document environmental impacts from the newest renewable energy technologies in production. While still in infant stage of development, tidal energy presents vast research opportunities for understanding short and long term effects on the ecosystem.

As noted above, in the case of Port Kembla’s MK3 test site for wave energy, they were able to successfully run this facility with almost no environmental impact. Before assessing these data it should be noted, however, that they were likely created by a company employee of Oceanlinx. It is unlikely that the information was inaccurately reported, but a degree of bias should be considered nonetheless. Some of the anticipated impacts and their results are listed in the Table 1.

Table 1: Summary of Environmental Impact Assessments of MK3

This information was directly published by an Oceanlinx employee, likely as a facet of the permitting process. There is a lot of useful data presented for the physical and human environment, but assessment of the biological environment is sparse. It provides very little information on the ecological and species impact. For example, the general conclusion regarding birds states that there should be no presence of birds in an industrial port without providing definitive scientific data to verify this claim. The other results simply regurgitate the same statement in regard to species impact, leading me to believe that very little data was gathered on biological during the environmental impact assessment, and thus presented little concern during the permitting process. Overall, the results were in favor of the MK3, but more data is necessary in order to assess the potential biological impacts without bias.

Conclusion

The wave energy experience at Port Kembla proved to be an important first step for the future development of wave energy technologies. The issues in gathering baseline data show that there needs to be a more streamlined framework for creating environmental impact assessments for wave energy devices. Moreover, the prolonged decommissioning of the Mk1 and Mk3 devices present a need for policies that create expedient deconstruction procedures for phasing out and removing old devices. Lessons learned from Port Kembla will be useful for moving forward in wave energy